Manufacturing of footwear has traditionally been a laborious process that involves cutting individual pieces and sewing the pieces together to form the footwear. However, this manufacturing process is batch-like in that a series of operations may be performed on a portion of the shoe by a first operator and then another series of operations, later in time, may be performed by a different operator. This start and stop process can lead to inefficiencies in the process.
Sewing pieces together also presents challenges if the shoe outer is not monochrome. It is often desirable to use the color of the stitching thread to complement the appearance of the shoe. In some designs, that might mean using matching thread to minimize the appearance of the stitching, contrasting threads to highlight the appearance of the stitching, or threads selected to form part of or otherwise accent a pattern, image, or design on the shoe. However, if the shoe is not monochrome, this requires changing the stitching thread, which is troublesome. Multiple thread types must be stocked, and the thread must be changed during manufacturing if a stitching line traverses two different colors or segments of the design on the shoe. Changing the thread adds time, cost, and complexity to manufacturing, and can exacerbate the number and duration of stops and starts in the process.